/**
 * Redis-compatible store. Works with any client that exposes:
 *   - `eval(script, numkeys, ...args)`  → number | string
 *   - `pttl(key)`                       → number (ms; -2 missing, -1 no ttl)
 *   - `get(key)`                        → string | null
 *   - `set(key, value, 'PX', ms)`       → 'OK'
 *   - `del(key)`                        → number
 *
 * Verified compat: `ioredis`, `node-redis` (v4+), `@upstash/redis` (HTTP,
 * works on Cloudflare Workers / Vercel Edge / Deno Deploy).
 *
 * Atomicity:
 *   - `incr` runs a single Lua script that INCR's the key and PEXPIRE's it
 *     only when the key is fresh (count == 1). TTL anchors to the first
 *     increment in the window — correct for fixed / token-bucket.
 *   - `read` runs a Lua script (GET + PTTL) so the snapshot is consistent
 *     even under contention.
 *
 * Optimization: when the client is `ioredis` (detected via `defineCommand`),
 * both scripts are registered once as named commands. Subsequent calls go
 * out as `EVALSHA`, saving the script body on every request.
 *
 * Namespacing: every key is prefixed with `rl:` by default so this adapter
 * doesn't collide with your application keys. Configurable via `prefix`.
 *
 * @param {object} client                 Redis-compatible client instance.
 * @param {{ prefix?: string }} [options]
 * @returns {import('../index.js').RateLimitStore}
 */
export function redisStore(client: object, options?: {
    prefix?: string;
}): import("../index.js").RateLimitStore;